Augmented-Reality Multimodal Cueing for Obstacle Awareness: Towards a New Topology for Threat-Level Presentation

The improved agility and flight control augmentation of Future Vertical Lift (FVL) aircraft will allow a variety of mission sets, extending the current helicopter reach to new terrains of operations such as high-altitude desert plateau and the urban canyons of megacities. To enable safe operations in degraded visual environments (DVE), the aircraft must be equipped with sensors that address visibility limitations to provide real-time 360° situation awareness (SA). Visual displays present inherent limitations due to partial representation of the threat space, because of their limited field-of-view (FOV) or their 2D exocentric perspective. Spatial auditory displays support a natural, ecologically valent, egocentric representation of space where auditory objects behave realistically in terms of direction, distance, and motion. Tactile displays also support a partial representation of 3D space, although with a lower resolution and typically limited to direction and motion. This paper discusses the recent development and evaluation of a sensor based static-obstacle threat assessment model for a trimodal obstacle avoidance display. The new threat assessment algorithm maps obstacle locations to threat levels in the vicinity of the vehicle and defines a direction-of-flight dependent Threat Space. The speed-dependent evolution of Threat Space is defined using a set of thresholds and linear equation parameters termed the Threat Space Parameters. The present paper reports on the determination of these parameters by four groups of U.S. Army and Navy pilots and the comparison between a stand-alone utility and inflight evaluation. The in-flight sessions were performed as part of the "360 SA" study conducted at the U.S. Army Aeromedical Laboratory (USAARL) and made use of their immersive, full-motion UH60 simulator. The purpose of the 360 SA study was to evaluate the proposed trimodal obstacle avoidance display as an addition to the Integrated Cueing Environment (ICE). The trimodal display suite consists of the ICE Collision Avoidance Symbology (ICE- CAS) displayed on the Primary Flight Display (PFD), an Integrated Collision Avoidance Display (ICAD) overlaying a panel-mounted terrain display (PMD), an Augmented-Reality Spatial Auditory Display (ARSAD), and the Tactile Situational Awareness System (TSAS). The current threat assessment and trimodal display, and its future evolution, are discussed in the context of pilot cueing synergies for the FVL multi-role platform.